Fix person in Bootstrap.md

Standardize person and audience across documentation.

Author: Amanda Butler

docs/reference/runtime/Bootstrap.md

@@ -2,12 +2,12 @@
 
 ### Entry points
 
-Mbed OS provides two entry points for developers to hook into:
+Mbed OS provides two entry points you as a developer to hook into:
 
 - `main(void)` - Default entry point. All the standard application code goes here.
-- `mbed_main(void)` - Executed directly before `main`. The user can define this.
+- `mbed_main(void)` - Executed directly before `main`. You can define this.
 
-When execution reaches the entry points, a user can expect a fully initialized system that is ready to execute application code. The Mbed OS boot sequence consists of four phases: target setup, toolchain setup, starting the RTOS and starting the Mbed application. You can see these phases below:
+When execution reaches the entry points, you can expect a fully initialized system that is ready to execute application code. The Mbed OS boot sequence consists of four phases: target setup, toolchain setup, starting the RTOS and starting the Mbed application. You can see these phases below:
 
 1. Set up target.
    1. Configure clocks.